NS_IMETHODIMP
nsListBoxBodyFrame::ScrollByLines(PRInt32 aNumLines)
{
PRInt32 scrollIndex, visibleRows;
GetIndexOfFirstVisibleRow(&scrollIndex);
GetNumberOfVisibleRows(&visibleRows);
scrollIndex += aNumLines;
if (scrollIndex < 0)
scrollIndex = 0;
else {
PRInt32 numRows = GetRowCount();
PRInt32 lastPageTopRow = numRows - visibleRows;
if (scrollIndex > lastPageTopRow)
scrollIndex = lastPageTopRow;
}
ScrollToIndex(scrollIndex);
// we have to do a sync update for mac because if we scroll too quickly
// w/out going back to the main event loop we can easily scroll the wrong
// bits and it looks like garbage (bug 63465).
// XXXbz is this seriously still needed?
// I'd use Composite here, but it doesn't always work.
// vm->Composite();
PresContext()->GetViewManager()->ForceUpdate();
return NS_OK;
}
nsresult
nsListBoxBodyFrame::ScrollByLines(PRInt32 aNumLines)
{
PRInt32 scrollIndex, visibleRows;
GetIndexOfFirstVisibleRow(&scrollIndex);
GetNumberOfVisibleRows(&visibleRows);
scrollIndex += aNumLines;
if (scrollIndex < 0)
scrollIndex = 0;
else {
PRInt32 numRows = GetRowCount();
PRInt32 lastPageTopRow = numRows - visibleRows;
if (scrollIndex > lastPageTopRow)
scrollIndex = lastPageTopRow;
}
ScrollToIndex(scrollIndex);
return NS_OK;
}
